Isochronizing and synchronizing system.



W/Messes:

P. M. RAINEY.

ISOCHRONIZING AND SYNCHRONIZING SYSTEM.

APPLICATION FILED AUG. 18. 1914.

Patented June 6, 1916.

2 SHEETS-SHEET lmvemar; Pau/ M M/hey UNITED STATES PATENT OFFICE.

PAULM. RAINEY, OF GLEN RIDGE, NEW JERSEY, ASSIGNOR, BY MESNE ASSIGNMENTS, TO WESTERN ELECTRIC COMPANY, INCORPORATED, A CORPORATION OF NEW YORK.

ISOCI-IRONIZING AND SYNCHRONIZING SYSTEM.

Specification of Letters Patent.

Patented June 6, 1916.

Application filed August 18, 1914. Serial N 0. 85?,309.

mechanisms operatively located at separated points on a transmission line.

Although it may be advantageously employed in many fields of endeavor, the invention finds a particularly ready adaptation in multiplex printing telegraphy, wherein it is essential that the rotatable current impulse distributors at'the transmitting and receiving stations operate in synchronism.

One of the prlncipal features of this invention is the improved method of and means for providing the initiation of isochronous rotation and the proper phase relation to secure synchronism between separated current distributers whereby, from an inactive state, operative conditions may be obtained with a minimum of adjustment and lossof time.

For the accomplishment of the above results, the invention contemplates the driving of the motor of the controlled distributer through current impulses governed by the controlling distributer and adjusting the source of motion of the controlleddistributer-until it can drive said distributer at the same speed as it is being driven by the impulses from the controlling distributer. The distributers are then in isochronism. When this condition obtains the adjusted sourceof motion is caused to drive the controlled distributer.

The invention further contemplates an adaptation of transmitted impulses and the hereinbefore mentioned mechanisms such that, after isochronism is obtained this condltion may, if necessary, be mpmentarlly 1nterrupted until corresponding elements of the distributers become cooperatively active,

or in other words, until the distributers are in phase, whereupon the synchronous relation will be fully set forth in the following description and claims, and will be more readily understood by reference to the accompanying drawings in which Figures 1 and 2, taken together, disclose the invention embodied in a system particularly applicable to multiplex printing telegraphs; Fig. 1 representing diagrammatically a portion of the apparatus at the controlling station, while Fig. 2 discloses the mechanism located at the controlled station. The controlling station is provided with a synchronous motor 10 which may be of the well-known La Cour or phonic wheel type, driven by the current impulses from an electromagnetic vibratory mechanism or reed 11. This reed may be, and preferably is, constructed like an ordinary tuning fork. The shaft of motor 10 operates a current distributer 13 which is composed of a contact arm 14 and conducting segments 15. The number of segments 15 is double the number of I poles of the rotor of motor 10, and they are normally divided into two equal groups composed of alternate segments, one group being connected to a positive source of electric energy 16 and the other to a negative source of electric energy 17, as shown. This arrangement, for a purpose to be hereinafter explained, may, however, be so altered by a key 18 that the segments are separated into 'two groups, each composed of consecutive.

segments over one-half the circumference. An arm 14 of distributer 13 is connected through the coil of a polarized relay 19 to a transmission line L, which leads to the distant controlled station. The system may be relay 19 and transmission line L, the frequency of such impulses depending upon the speed of vibration of the fork.

At the corrected station the transmission line L passes through the windings of a polarized line relay 20-and an artificial line AL, ina manner well known in the art. There is likewise a vibratory mechanism or fork 21 driven by a magnet 22 to cause the actuation of a synchronous motor 23. Motor has the same number of poles on its rotor as motor 10 at the controlling station, and operates a distributer 24 through a shaft 25 in the same manner as the apparatus at the controlling station. The period of vibration of fork 21 is adjustable by means of adjusting screw 26, which varies the effective length of the fork. This adjustment may be assisted by weights upon the prongs of the fork or any other suitable and well-known means. In addition to its operating magnet 22, the fork 21 is acted upon by a speed controller comprising a controlling or buffer magnet 31. The action of this vibratory mechanism and the manner in which current impulses maintain an isochronous condition between the controlling and controlled'distributers after such a condition is once obtained, are fully described and claimed in a copending application, Serial No. 827,315, filed March 26, 1914.

The shaft 25 carries a stroboscopic chart or disk provided with alternate black and white portions each twice innumber to the number of poles on the rotor of motors 10 and 23. These black and white portions,

h- 23 to be interchangeably driven by line 1mtwenty in number, may be viewed throug the shutters 36 secured to-the free ends of the prongs of fork 21. mirror 37 may be employed so that the stroboscopic disk may be viewed from some location other than inthe line of the shutter openings and the disk. It will be readily apparent that if motor 23 is driving disk 35 and fork 21 is started and its speed adjusted until the disk, when viewed through the shutters 36, appears to be stationary, the fork 21 and the motor 23 will be operating in cycles of equal duration.

The action of controlling magnet 31 is controlled by the controlling relay 40 whose action is governed by the current impulses on line L. When controlling magnet 31 is energized and its buffer limits the amplitude of vibration of fork 21, the frequency of the fork is increased in accordance with well-known physical principles. In order,

therefore, to have the bufi'er operate most advantageously to control the rotation of the distributer 24, the fork 21 should tend to vibrate too slowly when the controller magnet 31 is continuously dei nergized, and too rapidly when this magnet is continuously energized. It will therefore be readily apparent that the best condition to which to For convenience, a

windings of relays 20 and 41 are so arranged that when armature 42 of relay 20 is against its contact 43, armature 44 of relay 41 is also against its contact 45. The energization of relay 20 so that its armature 42 moves from the contact 43 to contact 46, causes the armature 44 of relay 41 to also move to its contact 47. The correcting segments of the distributor 24 are shown partly developed, alternate segments being normally connected together in two equal groups, one group connected to one winding of controlling relay 40 and the other group to the other winding of this relay. There are twice as many correcting segments as there are receiving segments, or four times as many segments as there are poles on the rotors of motors 10 or 23, and they are so arranged that a line midway between each pair of receiving segments comes on a line between a pairof correcting segments. With 9 this arrangement the correcting brush will always be interconnecting one of the two sets of correcting segments with the common correcting ring when a local correcting impulse is produced by the line impulses.

Means are provided for causing the motor pulses or impulses generated by its associated fork 21. An isochronizing switch is provided with live levers 51, 52, 53, 54 and 55 which are operated simultaneously, and all but levers 53 and 55 are equipped with-two contact points. Unlike the others, levers 53 and 55 have but one contact each. The levers 51 and 52 are connected through the two operating magnet circuits of motor 23 to a grounded source of energy 56, while their upper contacts and 61 are joined to the alternatecontacts of a circuit-switching or interrupter mechanism 62 on fork 21. The lower contact 63 of lever 51 and lever 53 are joined to contact 47 of relay 41, while the lower contact 64 of lever 52 is connected to contact 45 of relay 41. Contact 65 of lever 53 is connected to the common receiving ring of distributer 24, armature 42 of relay 20, through a resistance to one winding of relay 41, and from thence to ground and through the other windingof relay 41 and a resistance 71 to a source ofelectric energy 72. Levers 54 and are connected respectively 'to armature 44 of relay 41 and to a grounded source of energy 73. llpper contact 75 of lever 54 and contact T6 of lever are joined'to the common correcting ring of distributer 24, while lower contact 77 of lever 54 is grounded. In the normal or operating position all ofthe levers 51 to 55 43 and 46, co5perating with the armature 42 of leak relay 20, are respectively connected to a source of electric energy 75 and grounded. Relay 41 is polarized and its windings. the sources of energy 72 and 75, and resistance's and 71, are so proportioned and arranged that the flow of current from source 72. through one of the windings of relay 41 to the grounded point between the windings is overcome, to alter the position of armature .44, by current flowing in the other winding from source 75 when arma-. ture 42 is against contact 43. a

As previously stated, the normal arrangement of the correcting segments of distributer 24 is, two equal groups composed of alternate segments. This arrangement may, however, be altered to bring the correcting and corrected distributers into phase. A phasing switch is provided with two levers 81 and 82. Lever 81 is connected to one of the windings of relay 40, and also directly and by means of its left-hand contact 83 to one group of alternate correcting segments, while lever 82 is connected to the other winding of relay 40, and also directly and by means of its left-hand contact 84 to the other group of alternate correcting segments. When, however, switch 80 is thrown to the right, this condition is so altered that all of the consecutive correcting segments over one-half of the circumference of distributer24 make up a group, while all the consecutive segments over the other half of the circumference of distributer 24 make up another group. This alteration in the grouping of the correcting segments provides that .the corrective operation of relay 40, assuming that corrections are only made on line reversals from positive to negative, can only take place once per revolution of the corrected distributer. If, therefore, key 18 at thecorrecting station be now thrown to its off-normal position so as to connect consecutive segments over half the circumfercnce into groups to send out two pulses per revolution, it will be readily apparent that thei-e is only one point in the rotation of distributer 24 at which correcting magnet 40 may become operative. If the brushes of distributer 24 are behind the brushes of distributer 13 in phase, although traveling at the same speed, the correcting relay 40 and correcting magnet31 will cause the buffer to accelerate the speed of fork 21 and consequently di'tributer 24, until this distributer has gained an angle suflicient to bring the correcting and corrected distributors into phase. If, however, distributer 24 is ahead of distributer 13 in phase, correcting relay 40 and correcting magnet 31 will not be energized and the spring on the armature of magnet 31 will keep the buffer from engagement with the fork 21, and since, as previously pointed out, fork 21 when unaffected by the buffer tends to run too slow, the speed of distributer 24 will be momentarily decreased until it is in phase with distributer 13, whereupon the bufi'er will become active to hold the distributers in synchronism.

Assuming that the apparatus at both stations is at rest, the method of synchronizing the two distributers is as follows: Fork 11 is started-by hitting one of the prongs, or in any other well-known manner, whereupon, after the motor 10 is started, the fork operates the motor, causing the arm 14 driven thereby to sweep over contacts 15 sending impulses to line L. Any sort of a signal arrangement operating over a separate line, the duplex line L or any other suitable circuit, may be employed to allow intercommunication between the two stations during the synchronizing operations. Upon the receipt of a signal from the controlling station that the distributer 14 is in operation, or prior to his sending a signal to start this distributer, the operator at the controlled station throws the isochronizing switch 50 into its off-normal or isochronizing position.

The impulses on line L therefore actuate line relay 20, which, when its armature 42 is against contact 46, closes acircuit from ground, through resistance 70 and one winding of relay 41, to ground. In this condition the current from battery 72, through resistance 71 and the other winding of relay 41, keeps armature 44 against contact 47, and a circuit is completed from ground'at Contact 77, lever 54 of key 50, armature 44, contact 47, contact .63, lever 51, through one set of operating windings of motor 23, to grounded battery 56. Upon a reverse impulse on line L the armature 42 of relay 20 moves into engagement with contact 43, whereupon a circuit is completed-from battery 75, contact 43, armature 42, resistance 70, through one of current through this circuit overcomes that from battery 72 through the other winding of relay 41, and armature 44 engages .winding of relay 41, to ground. The flow current in line L, it Will be readily understood that motor 23 Will be driven at the brush alternately connects the two windings tion.

' half of the time, thisspeed of fork 21 is its of relay 40 to battery 73, through contact 76 and lever 55.' One set of these alternately connected segments energizing one winding of relay 4:0 to cause current 'to flowthrough magnet 31, while the other set of segments breaks the circuit through magnet 31. The

buffer is therefore against the prong of fork 21 one-half of the time, and removed therefrom the other half of the time. Fork 21, if not already in vibration, is thereupon started, and, by means of its adjusting screw and any other means employed, the speed thereof is regulated until when looking at the stroboscopic disk 35 through shutters 36 the disk appears to be stationary. The attendant then knows that fork 21 is vibrating at the correct speed to drive motor-23 and distributer 24 at the same speed as they are now being drivenfrom the controlling sta- Also since the bufler is in operation mean speed, which may be varied in either direction as required, to keep its motor 23 in isochronism with motor 10 at the controlling station. The switch 50 is now thrown into its normal position, as shown, whereupon fork 21 drives motor 23, and the line impulses serve not to drive this motor but to' exert a corrective influence thereover, as required, through relay 40 and magnet 31. Usually it is advisable to obtain this isochronous condition between the distant distributers with switch 80 in its off-normal position, whereupon, the buffer will be against the prong of fork 21 during half a revolution of motor 23, and away from the prong during the remaining half revolution. The result. is the same as when switch 80 is in its normal position, as shown. As previously stated, the correctingdistributer 13 and the corrected distributer 2 1 are now rotating in isochronism, this condition being insured by line reversals through the agency of relays 20, 4-1 and 10 and magnet 31, and it only, remains to bring the distributers into the proper phase relation or, inotherwords, to change the isochronous condition into a synchronous condition. If key 80 is not in its off-normal position, as just described, it is now so positioned, and the operator signals the operator at the correcting station to send corrective reversals, positive over half a revolution of distributer 13, andnegative over the other half revolution. Switch 18 is thereuponthrown to used-normal position. .Now since the correcting relay 40, as previously explained. is adapted to operate only on a reversal from positive to negative,

motors 10 and 23, segments 15, the correcting segments of distributer 2+1 and the black and white portions of stroboscopic disk 35, and while it is believedto be desirable to arrange the apparatus so that the appearance of rest for the disk 35 signifies the proper speed .of fork 21, it is to be understood that other arrangements are contemplated and may be used Without departing from the spirit of this invention. All that is necessary is to use such an arrangement and relation of parts that the attendant may know positively that fork 21 is vibrating at a speed such that it can operate motor 23. at the same speed as this motor is being operated from impulses fromthe correcting station.

The invention claimed is:

1. A method of isochronizing two'rotatable members operatively interconnected by a transmission line and adapted to be op: erated by independent sources of motion, which consists in operating one of said members by impulses over said line which are controlled by the other said member, adjusting one of the sources until it can drive its associated member at the same speed as it is being driven by the line impulses, and then causing said adjusted source to drive its associated member.

2. In an isochronizing system, the combination of a transmission line, a transmitting distributer for imparting current impulses to said line, a vibratory mechanism for driving said distributer, a receiving distributer, a variable vibratory driving mechanism therefor, means controlled by the line current reversals from said transmitting distributer to control said variable driving mechanism. a switch, and circuit connections whereby the control of said variable vibratory mechanism over said receiving distributer may be broken and said receiving distributer operated from the impulses from said transmitting distributer.

3. In an isochronizing sysium the combination of means for supplying current impulses, a transmission line for-carrying the current impulses, ameans for receiving the impulses, a motor for actuating saidineans. mechanism for driving said motor, and adjustable circuit connections whereby said motor may be driven by said mechanism or the impulses carried by said line.

4. An isochronizing system comprising a current impulse distributer, phonic motor, and vibrator at a controlled station; a current impulse distributer, synchronous motor, vibrator, and speed controller devices, at a controllin station; a transmission line interconnecting said distribu't/ers; and an isochronizing switch and circuit connections controlled thereby for interchangeably causing said motor and said distributerat the controlled station to be driven by current vimpulses from said line or by said vibrator at the controlled station. I

5. A method ofsynchronizing two rota- I table members operatively interconnected by a transmission line and vadapted to be op-' 'erated by independent sources of motion,

which consists in operating one of said members by impulses over said line controlled by the other said member, adjusting one of the sources until it can drive its associated member at the same speed as it is now being driven by the line impulses, then causing said adjusted source to drive its associated member, and. lastly momentarily altering the speed of the adjusted source so that its assecond mentioned motor to be driven by line current impulses or by said second mentioned vibrator, a second switch and circuit connections for altering the condition of said speed controller, and means for affecting the condition of the controlling distributer.

In Witness whereof, I hereunto subscribe my name this 14 day of August, A. D. 1914.

PAUL M. RAINEY.

Witnesses:

E. Elohim, N. E. TUTHILL. 

